package com.easypan.entity.dto;

import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.io.OutputStream;
import java.io.Serializable;
import java.util.Random;

public class CreateImageCode {

    // 图片的宽度。
    private int width = 160;
    // 图片的高度
    private int height = 40;
    // 验证码字符个数
    private int codeCount = 4;
    // 验证码干扰线数
    private int lineCount = 20;
    // 验证码
    private String code = null;
    // 验证码图片buffer
    private BufferedImage buffImg = null;
    Random random = new Random();

    public CreateImageCode() {
        creatImage();
    }

    public CreateImageCode(int width, int height) {
        this.width = width;
        this.height = height;
        creatImage();
    }

    public CreateImageCode(int width, int height, int codeCount) {
        this.width = width;
        this.height = height;
        this.codeCount = codeCount;
        creatImage();
    }

    public CreateImageCode(int width, int height, int codeCount, int lineCount) {
        this.width = width;
        this.height = height;
        this.codeCount = codeCount;
        this.lineCount = lineCount;
        creatImage();
    }

    // 生成图片
    private void creatImage() {

        int fontWidth = width / codeCount;// 字体宽度
        int fontHeight = height - 5; // 字体的高度
        int codeY = height - 8;

        // 图像buffer
        buffImg = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
        Graphics g = buffImg.getGraphics();
        // Graphics2D g = buffImg.createGraphics();
        // 设置背景色
        g.setColor(getRandColor(200, 250));
        g.fillRect(0,0,width,height);
        // 设置字体
        Font font = new Font("Fixedsys", Font.BOLD, fontHeight);
        g.setFont(font);
        // 设置干扰线
        for (int i = 0; i < lineCount; i++) {
            int xs = random.nextInt(width);
            int ys = random.nextInt(height);
            int xe = xs + random.nextInt(width);
            int ye = ys + random.nextInt(height);
            g.setColor(getRandColor(1,255));
            g.drawLine(xs,ys,xe,ye);
        }
        // 添加噪点
        float yawpRate = 0.01f; // 噪声率
        int area = (int) (yawpRate + width + height);
        for (int i = 0; i < area; i++) {
            int x = random.nextInt(width);
            int y = random.nextInt(height);
            buffImg.setRGB(x,y,random.nextInt(2550));
        }

        String str1 = randomStr(codeCount); // 得到随机字符
        this.code = str1;
        for (int i = 0; i < codeCount; i++) {
            String strRand = str1.substring(i,i+1);
            g.setColor(getRandColor(1,255));
            // g.drawString(a,x,y)
            // a为要画出来的东西，x和y表示要画的东西最左侧字符的基线位于此图形上下文坐标系的(x,y)位置处
            g.drawString(strRand,i * fontWidth + 3, codeY);
        }

    }

    // 得到随机字符
    private String randomStr(int n) {
        String str1 = "ABCDEFGHJKLMNOPQRSTUVWXYZabcdefghijkmnpqrstuvwxyz123456789";
        String str2 = "";
        int len = str1.length() -1;
        double r;
        for (int i = 0; i < n; i++) {
            r = (Math.random()) * len;
            str2 = str2 + str1.charAt((int)r);
        }
        return str2;
    }
    // 得到随机颜色
    private Color getRandColor(int fc, int bc) { // 给定范围获得随机颜色
        if (fc > 255) fc = 255;
        if (bc > 255) bc = 255;
        int r = fc + random.nextInt(bc - fc);
        int g = fc + random.nextInt(bc - fc);
        int b = fc + random.nextInt(bc - fc);
        return new Color(r,g,b);
    }

    public void write(OutputStream sos) throws IOException {
        ImageIO.write(buffImg,"png",sos);
        sos.close();
    }

    public BufferedImage getBuffImg() {
        return buffImg;
    }

    public String getCode() {
        return code.toLowerCase();
    }

}
